In order to effectively enhance a network coverage and a system capacity, the 3rd Generation Partnership Project (3GPP) is currently studying the deployment of Small cells in a Long Term Evolution-Advanced (LTE-A) system. As compared with an original Macro evolved NodeB (eNB), the Small cell has relatively small transmission power and coverage. In addition, the small cell is usually deployed within the coverage of the Macro eNB, so as to enhance the network coverage and the system capacity.
In the case that a terminal (also called user equipment, UE) is located within the coverage of the Macro eNB and the Small cell, a Radio Resource Control (RRC) connection may be simultaneously maintained between the terminal and the two base stations, i.e., the terminal may be served by the Macro eNB and the Small cell at the same time, and two physical links may be maintained between the terminal and the Macro eNB and the Small cell. At this time, this network architecture may be called as dual-connectivity network architecture (as shown in FIG. 1). It should be appreciated that, through the dual-connectivity technique, it is able to effectively increase an uplink/downlink bit rate of the terminal, enhance the system capacity, optimize the signaling and improve the mobility robustness. It should be further appreciated that, in a dual-connectivity scenario where the terminal is served by the Macro eNB and the Small cell, one of them may be taken as a Master eNB (MeNB) for the terminal, and the other may be taken as a Secondary eNB (SeNB) for the terminal. The MeNB is mainly used to assist the terminal in the management of control plane-related information, and the SeNB is mainly used to provide the terminal with corresponding radio resources. FIG. 2 shows the data transmission for a user plane and the control plane of the terminal during the dual-connectivity state. In FIG. 2, the macro cell is the MeNB, and the small cell is the SeNB.
In other words, as shown in FIG. 2, in accordance with the conventional dual-connectivity architecture, in the case that the terminal accesses a network, core network control nodes, for example, a Mobility Management Entity (MME), may issue information, such as a service bearer desired to be established by the terminal and corresponding QoS parameters for granting the QoS of the terminal (e.g., UE-Aggregate Maximum Bit Rate (UE-AMBR, which is suitable for the bearer with a non-granted bit rate and which may further include UE-AMBR in an uplink direction from the terminal to the base station and UE-AMBR in a downlink direction from the base station to the terminal), Maximum Bit Rate (MBR, which is suitable for the bearer with a granted bit rate and which may further include MBR in the uplink direction from the terminal to the base station and MBR in the downlink direction from the base station to the terminal), and Granted Bit Rate (GBR, which is suitable for the bearer with a granted bit rate and which may further include GBR in the uplink direction from the terminal to the base station and MBR in the downlink direction from the base station to the terminal)), to the MeNB that assists the terminal in the management of control plane-related information, rather than to the SeNB. In this regard, the SeNB does not have the information about the QoS parameters. Therefore, in the case that the terminal is served by the MeNB and the SeNB simultaneously in the dual-connectivity scenario, a service provided to the terminal may not match the QoS that should have been possessed thereby. For example, the terminal may acquire an overall bit rate greater than the UE-AMBR, or a maximum bit rate greater than the MBR, resulting in a waste of the network resources, and a decrease in an overall resource utilization rate as well as the overall performance of the network.